Loudspeaking intercom system

Claim 1

IN A LOUDSPEAKING INTERCOMMUNICATION SYSTEM HAVING A MASTER AND A REMOTE STATION, MASTER STATION AMPLIFYING MEANS HAVING INPUT AND OUTPUT CIRCUITS, AND ELECTROACOUSTIC TRANSDUCER LOCATED AT EACH OF SAID MASTER AND REMOTE STATIONS, SAID TRANSDUCER AT SAID REMOTE STATION BEING A BIDIRECTIONAL TRANSDUCER, MEANS FOR CONNECTING SAID TRANSDUCER AT SAID MASTER STATION TO SAID OUTPUT CIRCUIT, INTERSTATION CIRCUITS EXTENDING FROM SAID MASTER STATION TO SAID REMOTE STATION, MEANS FOR CONNECTING SAID BIDIRECTIONAL TRANSDUCER AT SAID REMOTE STATION TO SAID INTERSTATION CIRCUITS, MEANS FOR CONNECTING SAID INTERSTATION CIRCUITS TO SAID INPUT CIRCUIT, PRIVACY SWITCH MEANS LOCATED AT SAID REMOTE STATION HAVING OPERATIVE AND INOPERATIVE CONDITIONS, MEANS LOCATED AT SAID MASTER STATION FOR MUTING SAID AMPLIFYING MEANS, AND MEANS INCLUDING SAID INPUT CIRCUIT CONNECTING MEANS FOR CONTROLLING SAID MUTING MEANS IN ACCORDANCE WITH THE OPERATIVE CONDITION OF SAID SWITCH MEANS WHEREBY PRIVACY AT SAID REMOTE STATION IS UNDER THE CONTROL OF THE OPERATOR AT THE REMOTE STATION.